Nuclear-capable stealth bombers drill over Korea

The United States has revealed two of its nuclear-capable B-2 stealth bombers have carried out firing drills over the Korean peninsula.

The state-of-the-art bombers flew from a base in the US state of Missouri in what has been called a long-duration, 20,800km round-trip training mission.

"This... demonstrates the United States's ability to conduct long-range, precision strikes quickly and at will," the US military said in a statement.

"The B-2 bomber is an important element of America's enduring and robust extended deterrence capability."

The US-South Korea joint drills are held every year and are regularly condemned by Pyongyang as rehearsals for invasion.

This week North Korea put its rocket units on combat status and threatened to strike US bases in Hawaii, Guam and on the American mainland after recent flights over the peninsula by older B-52 bombers.

The North also severed its last-remaining military hotline with South Korea, saying it was no longer needed given that "war may break out any moment".

While most analysts have dismissed the bulk of the North Korean threats as rhetorical bluster, there are concerns that even a minor incident could swiftly escalate in such a volatile environment.